Ore-grinding mill



Feb. 10, 1925.

J. W. COVER ORE GRINDING MILL Filed Aug. 11, 1924 2 Sheets-Sheet 1 gwuehtoz W Cover album:

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Feb. 10. 1925.

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Filed Aug. 11, 19 4 2 Sheets-Sheet 2 F gmwfm John N. Cave? Patented Feb. 10, 1925.

UNITED STATES 1,525,919 PATENT OFFICE.

JOHN W. COVER, OIE SEATTLE, WASHINGTON, ASSIGNOR T0 LO DE DREDGE 00., OF

SEATTLE, WASHINGTON, A CORPORATION OF WASHINGTON.

ORE-GRINDING- MILL.

Applieation filed August 11, 1924. Serial No. 731,280.

To all whom it may concern:

Be it known that I, JOHN W. COVER, a citizen of the United States of America, and resident of the city of Seattle, in the county of King and State of Vashington, have invented certain new and useful Improvements in Ore-Grinding Mills, of which the following is a specification.

My invention relates to that kind of a grinding mill employed for grinding ores and other analogous work, commonly re ferred to as a bar mill, the same employing a series of loose bars or rods confined within a casing and caused to roll and slide upon themselves by revolution of the casing.

The object of my invention is to provide improvements in the detailed construction of such a mill which will facilitate the making and maintenance thereof and its operation.

My invention consists of the novel features which will be first described and then specifically defined in the claim.

The accompanying drawings show my invention in its present preferred form.

Figure 1 is alongitudinal section through a drum having the construction which forms the subject of my present invention.

Figure 2 is a side view of one of the trackway rings.

Figures 3 and 4: are cross sections of alternate forms of construction for the abutment plate or head.

The present invention is an improvement upon the type of mill shown in United States Patent No. 1,242,423, issued to me October 9, 1917. The parts which constitute my invention are included in the construction of the drum and its contents. The entire mounting of the mill has not, therefore, been shown. This may be such as shown in said patent or of any other type found suitable.

The drum 1 is supposed to have screens for the passage of water and finely ground material, either such as shown in said patent or of other suitable construction, Within the drum, and secured thereto, are two trackway rings 2, These are supported inwardly from the d m as y the e o fee r egs 20, clearly shown in Figure 2. Within these t ckway r ng a e pl e a bun h o rod or bars as 21.

The material to be ground is introduced through one or the other of the hollow jour nals 10 upon which the mill is supported and turned. The drum is provided with ledges or plates 11 extending a short distance inward from the shell, these serving to raise a portion of the ore or other material being ground and depositing it upon the mass of the rods which do the grinding. This, is similar in construction to that shown in my said patent.

It has been found that in a rod mill of this type the rods will shift somewhat endwise and will contact with the head of the drum if this be permitted, thereby tending to Wear out the head of the drum. counteract this and. for other reasons, I have, in the present invention, provided an abutment head 3 located one in each end of the drum, and have supported these from the drum or the head thereof so that they are separated slightly more than the length of the rods employed. These abutment heads may be made of heavy castings which are easily and cheaply made, as they do not require machine finishing. Therefore, when worn out they may be cheaply replaced. This may be done at much less cost than replacing the true head of the drum.

In the type of construct-ion shown the abutment heads 3 are supported by legs 30 which may be cast integral therewith or attached thereto. These legs, in Figure 1, are shown as extending to and carried by the heads 12 of the drum. lVhether carried by the heads 12 or by the outer shell of the drum is immaterial. I have also shown the abutment heads 3 as provided with a central hole of considerable size, in which is secured a smaller head 31. This latter head may entirely close the opening in the head 3 or it may be provided with a central head 32 through which a rod may be inserted for carrying a deflector plate such as is shown in my previously mentioned patent, or a pipe for carrying water.

For convenient insertion and removal of the grinding rods 21, I provide at least one of the abutment heads 3 with an opening, preferably spaced from the center so that its outer edge approximately corresponds with the track-way surface of the rings 2, This opening is also in alinement in the direction of the axis of the drum, with a c mp emen a pe ng n he h ad. 12 oi the drum. It is evident that with holes so placed, of a. size to pass the grinding rods, these may be very conveniently inserted and may also be removed without difficulty. WVithout provision of such means the insertion or removal of these rods after the drum has been assembled would be a very diiiicult, it not an impossible, matter.

The holes above described are, when the drum is in use, closed by a plug device shown at the right hand end of Figure 1. This device has a head 4 which snugly fits the opening in the abutment head, the inner end face of the plug alining with the inner surface of the abutment head. The shaft 40 of this plug connects the head 4: with the head 41 which is so shaped and of such size as to fit the opening in the head 12 of the drum. This may be clamped in place with packing materialso as to maintain a water tight joint. By the removal of this plug it is thus possible extract or replace the grinding rods.

I have illustrated in the drawing the drum 1 as mounted to turn upon hollow journal extensions 10, one at each end. These turn in suitable bearings. The manner of mounting this for turning is, however, immaterial. This may be done by mounting it upon rollers as was illustrated in my previous patent above referred to.

In Figure 1 I have shown the abutmentheads 3 as having a plane surface without any flanges at the outer edges. These abutment heads may be constructed after the form shown in Figures 3 and in which flanges as 33 and 84: are shown surrounding the outer edge of the heads. These serve as additional means for retaining the rods in place. The curved flanges 84, when used will also serve to somewhat crowd the rods toward the central position.

What I claim as my invention is:

In a bar mill, a drum, trackway rings having their trackway surface inwardly spaced from the inn-er periphery of the drum, abutment disks of smaller diameter than the drum located between the ends of the bar and the drum heads, one of said abutment disks and its adjacent drum head having alined holes permitting passage of the grinding rods and av stopper adapted to close both of said openings and secured to the drum head.

Signed at Seattle, King County, lVashington, this 31st day of July, 1924.

JOHN WV. COVER. 

